470 QUEENSLAND AGRICULTURAL gouRNAL. [1 Juns, 1899. 
USE OF THE PLOUGH. 
A cloddy soil will certainly defeat all efforts to get a good and uniform 
stand in the field, and care should be taken to plough the ground when it is in 
proper condition. A tobacco-field should be ploughed after each hard rain— 
after the ground has sufficiently dried, until the plant is too large. When the 
plants are kept in a perfectly healthy and vigorous condition, they are less 
susceptible to disease. Pruning, or taking off the bottom leaves mn order to 
allow ventilation under the plant, is also a condition to healthy fields. The 
amount of water in the soil to produce the best results for heavy pipe tobaccos 
is estimated to be from 15 to 20 per cent. : 
“Below 15 per cent. the line of drought is reached, and the methods of 
cultivation should have for their prime object the maintenance of the water 
supply above the line of drought, so that the growth of the plant shall receive 
no check.” —Whitney. 
PRODUCT. 
Ié is important that growers should take notice of these things, for when 
they seek an outlet for the surplus product they must offer an article quite as 
good as others, and one which is produced as cheaply. This cannot be done 
unless the best methods are adopted—the best are the most economical. 
The appreciation of the necessity of proper methods, and their adoption, 
will save fully 25 per cent. of labour, besides giving better and increased results. 
The various pests of the tobacco plant can be controlled by the use of 
Paris green, as a spray, but this must not be used after the tobacco has been 
topped. It is very effective in the case of the Miner. ; 
The lands best suited to growing heavy export or pipe tobaccos are friable 
and well drained. Limestone soils, with a small percentage of clay and a large 
percentage of silt, are the best. Wet or forcing soils will not grow good tobacco, 
as the product will be rank and woody. : 
Climate has much to do with the quality, and this can only be determined 
by experiment. For cigar tobacco sandy soils are preferred, some of the best 
cigar lands of Florida having 50 per cent. of sand. This is confirmed by Mr. 
Whitney in his report on the tobacco soils of the United States. 
MANURING OF TROPICAL PLANTS. 
ORANGES AND LEMONS. 
Investigations conducted by Dr. Hilgard* (California) have shown that 
oranges and lemons remove the following quantities of plant-food ingredients 
from one acre :— ' 
Phosphoric 
Potash. Acid. Nitrogen. 
1. 20,000 lb. oranges... 42°21b. «.. =: 10°6 Ib... ~— 3 6°6 Ib. 
2. 20,000 lb. lemons PEE 5 3 See see ene 2:2 mee 30322 ee 
No attention was paid in these tests to the quantities of plant-food 
ingredients present in the wood and leaves, and as these are by no means 
insignificant the above figures must be considerably increased if we would 
obtain the exact supply of plant-food required annually by orange and lemon 
fields. Results of practical investigations from which to compile figures 
regarding the total quantity of plant-food are, however, not at hand. 
But little material of practical value with regard to the cultivation of these 
fruits exists, and that is based upon the experience of American planters, no 
important conclusions having as yet been reached in Europe. 
Dr. Woodbridge reports some interesting results, relative to orange 
fertilisation, obtained from trials conducted at North Pomona, Southern 
California, which were begun in January, 1893. The plots, each containing 10 
orange-trees, were manured at that time, as shown in the table below, the 
aE ABN of the Work of the Agricultural Experiment Station of the University of California, 
